<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <link rel="icon" type="image/png" href="images/logo1.png" />
    <style>
        .red {
            background-color: red;
            width: 100px;
            height: 100px;
            float: left;
        }
        .green {
            background-color: green;
            width: 100px;
            height: 100px;
            float: left;
        }
         a {
            background-color: purple;
            
        }
    </style>
</head>
<body>
    <div class="a">
        <div class="red">我是红色</div>
        <div class="green">我是绿色</div>
        <div class="red">我也是红色</div>
    </div>
  
</body>
</html>